be difficult of definition的意思|示意

Finding a universal definition of marriage, though, has proven to be difficult.

尽管要对婚姻进行定义确实困难重重。

Since we don't have a very precise machine definition of what it means to be - for a meme to be truthy, it's really difficult to tell how to best do that.

我们对此没有非常精确的机械定义--要让一条发言看起来更真实，很难说怎么做最好。

When using various skins and styles, it sometimes becomes difficult to keep track of which style definition will be used for a particular class.

在使用多种皮肤和样式时，有时很难知道某个特定的类使用的是哪个样式定义。